Flame arresters for spark ignited internal combustion engines are generally known. Typically, the flame arrestor doubles as the air inlet for non-boosted engines and includes a circuitous flow path to minimize flame propagation back out through the air inlet. For example, disk-type flame arresters are known which include a peripheral side ambient air inlet and a bottom outlet mounted to a carburetor covering one or more top facing barrels. During an engine backfire, flames propagating upward from the barrels into the bottom outlet of the flame arrestor are squelched before exiting out through the peripheral side inlet.
In boosted internal combustion engines, such as by supercharging and/or turbocharging, it is desirable to locate a flame arrestor downstream of the boost device and associated engine manifolding to prevent high temperature gasses or flames from propagating back into and igniting gasses in the engine manifolding. Unlike flame arresters for non-boosted engines in which the operating environment is typically ambient temperature and pressure, flame arresters for boosted engines must operate in high temperature and high pressure environments as a result of the work performed on the intake air during compression. Further, in many applications, fuel-rich gasses are also present in the engine manifolding and increase the risk of explosion, despite aftercooling to reduce the boosted intake air temperature.
What is needed is a flame arrestor that prevents flame propagation from the combustion chamber in high temperature and high pressure operating environments, while still providing air to the combustion chamber intake with minimum pressure drop. Preferably, such a flame arrestor should be particularly suited to boosted internal combustion engines. In particular, the flame arrestor should be capable of preventing flame propagation into upstream engine manifolding during repeated engine backfires. Ideally, the flame arrestor should be durable and easily manufactured.